am 7e997388: am b5e21103: Merge "AArch64: Use LDXR/STXR instead of LDAXR/STLXR for bionic_atomic_cmpxchg()"

* commit '7e997388ba63f0b0b4c95542cfc5fbe6e3c93b4d':
  AArch64: Use LDXR/STXR instead of LDAXR/STLXR for bionic_atomic_cmpxchg()